Josh Rachford, a friend of mine from Tumblr’s early days, jokingly asked on Twitter:
What’s a normal dose of chocolate covered espresso beans? 30-40?
Actually, chocolate-covered espresso1 beans aren’t as highly caffeinated, relative to most coffee, as people think.
Disclaimer: I am not a doctor or a nutritionist and I have absolutely no qualifications to make any of these claims. The only research I’ve done on this topic is from the internet and my kitchen scale. Do not base any decisions on this blog post, ever. Also, these numbers are very imprecise, since they all vary a lot depending on how much coffee you use and how you make it. But this is a good ballpark.
A typical 8-ounce mug of coffee, if made properly (which most people would consider too strong), was brewed from about 12 grams of beans. That’s about 100 beans, and it will contain about 120 mg of caffeine, yielding approximately 1.2 mg of caffeine per coffee bean.2
Dark chocolate is usually about 0.8 mg of caffeine per gram.
Chocolate-covered espresso beans usually contain 1-3 grams of dark chocolate and one coffee bean. So they’re likely to contain approximately 2-4 mg of caffeine each. It’s worth noticing here that, depending on its thickness, the chocolate might contain more caffeine than the coffee bean.
Since the typical mug3 of coffee is about 120 mg of caffeine, it’s roughly equivalent to the caffeine levels of 30 of these theoretical chocolate-covered beans. (The buzz you get from eating a bunch of them is also partially attributable to the sugar in the chocolate.)
If you can handle the caffeine from that mug of coffee, you should expect a similar-strength buzz — albeit with a lot more sugar, which I certainly wouldn’t advise — from about 30 chocolate-covered beans.
So Josh actually, and probably inadvertently, nailed it.
There’s no such thing as an “espresso bean” — beans labeled as such are usually just coffee beans, of unspecified origin, with a dark roast. ↩
Different brewing methods can have higher or lower caffeine-extraction ratios — how much of the caffeine is actually released into the coffee — but, in practice, since caffeine is highly water-soluble, most drip brews extract nearly all of it fairly quickly. So it’s probably safe to assume that drinking drip-brewed coffee will yield approximately the same amount of caffeine as if you had eaten the amount of beans that it was made from. ↩
If you get your coffee from Starbucks, your typical cup might contain much more coffee. A “tall” (12-ounce) regular coffee there, for instance, is usually at least 260 mg of caffeine, partially because the cups are so large and partially because they use a very high beans-to-water ratio (and very dark roasts) to achieve (mediocre) flavor from stale beans. I can’t drink Starbucks’ coffee — even if I could get past the taste — because it’s far too much caffeine for me to handle. ↩